Wilhelm Gottfried Liebniz was born on July 1, 1646, and his first paper about integral calculus was published 329 years ago. Whether he discovered calculus before or after Newton is an issue that mathematical historians have debated for centuries.

Honestly, who cares? Both were great mathematicians. Still, it’s fun to think about how this issue might play out if they were both alive today…

My wife forwarded an email with a link to a CNN article and subject line, “Your husband will love this.” Uh-oh. Even my closest friends cannot correctly predict what I will and will not love, so how would a colleague of my wife — who only knows me from an introduction at a professional reception — be able to make such a prediction?

They [Lays Stax] set themselves up as a Pringles competitor, but it’s an entirely different curvature!

I have never met the author, but her last name was familiar. As luck would have it, her math professor husband and I taught together at a gifted camp for several summers. Small world, eh?

My favorite line of the article was from the last paragraph.

Flavor is subjective. Math is irrefutable.

Fact.

What I enjoyed most about this occurrence was the intersection of several math topics. The article discusses parabolic cylinders and hyperbolic paraboloids, which are topics in multivariable calculus; a colleague of my wife forwarded a link about an article written by the wife of a former colleague, which demonstrates social network theory; and, a colleague of my wife is not equivalent to the wife of my colleague, which shows non‑commutativity.

Teacher: If you have $4, and you ask your father for another dollar, how much would you have?

Johnny: Four dollars.

Teacher: Young man, you don’t know your addition facts!

Johnny: Ma’am, you don’t know my father!

Johnny’s father and my dad seem to have a lot in common. But my dad would have been proud of me yesterday. While walking home from the local coffee shop, I noticed a corner of a dollar bill on the ground. Not the whole bill, mind you, just a corner that had been ripped off. I thought not much of it, until two feet later I saw another scrap of the dollar bill… then another… and another…

I know and understand Calculus, and I realized that a lot of little things can add up to a lot, so I spent 15 minutes scouring the area for as many pieces of the dollar bill as I could find. I took them home and asked my sons, “Wanna do a puzzle?” We spent a half-hour reconstructing the bill and taping it together. The pictures below show the before and after:

The bill was not in good enough shape to be accepted by a vending machine (too much tape, I suspect, and the missing piece on the right side surely didn’t help, either), but it was in good enough shape for my bank to give me four shiny quarters in exchange for it.

I know that a penny saved is a penny earned. But what is a dollar found?

And the bigger question: What should I do with my new-found wealth?

I decided to buy a lottery ticket. The state gambling commission organized a raffle that boasted an infinite amout of money as the prize. To my great surprise, I won! When I showed up to claim the prize, they told me it would be disbursed as 1 dollar now, 1/2 dollar next week, 1/3 dollar the thrid week, 1/4 dollar the week after that, and so on.

But the joke’s on them. My winnings for the third week will include a one-third cent piece, and that’s gotta be worth something, right?

(Note: Almost everything above is true. I really did find the pieces of a dollar bill on the ground yesterday. As best I can tell, the bill had been on the lawn when it was cut by the blades of a power mower. And my bank really did give me four quarters in exchange for the taped-up, reconstructed version.)

The day before mid-term exams, the calculus professor allowed 10 minutes at the end of class for questions.

When one student asked the professor how many problems would be on the exam, the professor replied, “I think you will have a lot of problems on the exam.”

“Well, sir,” the student continued, “do you have any suggestions for what I can do to prepare?”

“Yes,” he said. “Just study the old exams. The mid-term exam will have the same types of problems, just the numbers will be different. But not all of the numbers will be different. Both π and e will be the same, of course, and there’s a reason it’s called Planck’s constant…”

Before dismissing the class, the professor warned that there would be no acceptable excuses for missing the exam.

About MJ4MF

The Math Jokes 4 Mathy Folks blog is an online extension to the book Math Jokes 4 Mathy Folks. The blog contains jokes submitted by readers, new jokes discovered by the author, details about speaking appearances and workshops, and other random bits of information that might be interesting to the strange folks who like math jokes.